Negative pressure preventive device in refrigerator

ABSTRACT

A negative pressure preventive device in a refrigerator is provided to be mounted to a machinery room on a top side of the refrigerator, in which an opening and closing damper is provided over an evaporator for controlling external air such that warm external air is led through an evaporator to reduce a temperature difference while the warm external air passes through the evaporator for minimizing a temperature change in the refrigerator, the opening and closing damper has a control lever operative by gravity to make quick and accurate opening, closing, and air introduction to the refrigerator for compensating a pressure difference, a filter mounted to the opening and closing damper at an air introduction portion to be detachable with a packing cap for easy removal of noxious insects, microbes, and dust, and easy washing and replacement, and a packing member provided to the opening and closing damper for improving a sealing function to prevent cold air from leaking, quick compensation of the pressure difference, and eliminating difficulty in opening the door caused by the negative pressure.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The present invention relates to a negative pressure preventive device in a refrigerator, and more particularly to a negative pressure preventive device in a refrigerator which can introduce external air to the refrigerator by means of a negative pressure preventive device to eliminate a pressure difference between an inside and an outside of the refrigerator at the time of opening of a door of the refrigerator for making opening of the door easy, with the external air introduced to the refrigerator made to pass an evaporator for heat exchange to prevent a temperature of the refrigerator from rising and to compensate a pressure difference quickly at the time of door closing, for preventing the door from becoming difficult to open due to the negative pressure.

2. Discussion of the Related Art

The refrigerator is provided with a compressor for compressing gaseous refrigerant to high pressure and high temperature refrigerant, a condenser for condensing the gaseous refrigerant compressed at the compressor into liquid refrigerant, a capillary tube for converting the liquid refrigerant into a low temperature and low pressure refrigerant, and a cooler for evaporating the low temperature and low pressure refrigerant from the capillary tube to absorb latent heat from surrounding air to cool down the surrounding air. By supplying the cooled air around the cooler to a freezing chamber and a refrigerating chamber, insides of the freezing chamber and the refrigerating chamber are cooled down.

Food in the refrigerator is maintained freshness, and can be frozen. And, when the door is opened for taking out or putting in the frozen or refrigerated food, the external air is introduced to the refrigerator, and shrinks quickly to cause the negative pressure in the refrigerator, i.e., an intensive pressure difference between an inside and an outside of the refrigerator. When a user intends to open the door again, since the negative pressure causes difficulty in opening the refrigerator door to require a great force, the old and the weak experience inconvenience as they can not open the door, easily.

In more detail, when the user closes the door after using the refrigerator, since the external warm air introduced to the refrigerator shrinks rapidly by a low temperature in the refrigerator to cause the negative pressure which makes strong adhesion of the door to a refrigerator body as much as the pressure difference between the door and the refrigerator body, opening of the door becomes difficult to require the great force, such that the old and the weak experience inconvenience in using the refrigerator.

Moreover, since the negative pressure in the refrigerator causes infiltration of relatively humid and warm air into the refrigerator through a gap between a gasket and an edge portion of the refrigerator, the negative pressure causes problems in that the relatively humid and warm air infiltrated into the refrigerator forms frost on the evaporator making refrigerator efficiency poor, and infiltration noise makes the user unpleasant.

There have been many technologies disclosed for improving such problems by using the negative pressure preventive devices in this field of art.

As a related art technology, the U.S. Pat. No. 4,257,445 discloses a configuration in which an external air passage is provided on an outside wall of a refrigerator, with an opening and closing damper elastically mounted thereto with a spring, such that the flow passage is opened by a pressure difference caused by the negative pressure generated in the refrigerator to introduce external air to the refrigerator, and, if the pressure difference is eliminated thus, the flow passage is closed by the elasticity of the spring. However, the configuration has problems in that the spring on the opening and closing damper forms rust on the metal spring, and is liable to cause defect, the external air introduced to the refrigerator through the flow passage formed directly in the refrigerator liable to carry various external harmful microbes, and the introduction of the large amount of external air to the refrigerator results in a temperature rise in the refrigerator.

As another related art technology, the U.S. Pat. No. 5,573,323 discloses a configuration in which the opening and closing is made easy by eliminating a pressure difference between an inside and an outside of the refrigerator with external air introduced to the inside of the refrigerator through a space formed between a soft packing member and a close contact portion of a refrigerator body by pressing the packing member mounted to a refrigerator door with an opening and closing plate interlocked with a pedal to be pressed by one foot. However, the configuration is complicate with the pedal and the opening and closing plate interlocked with the pedal, to cause difficulty in fabrication, and drawbacks of high cost, and many defects.

Thus, many similar technologies in the related art have problems in that configuration is complicate, or elimination of the negative pressure of the refrigerator is not quick.

SUMMARY OF THE DISCLOSURE

Accordingly, the present invention is directed to a negative pressure preventive device in a refrigerator.

An object of the present invention is to provide a negative pressure preventive device in a refrigerator to be mounted to a machinery room on a top side of the refrigerator, in which an opening and closing damper is provided over an evaporator for controlling external air such that warm external air is led through an evaporator to reduce a temperature difference while the warm external air passes through the evaporator for minimizing a temperature change in the refrigerator, the opening and closing damper has a control lever operative by gravity to make quick and accurate opening, closing, and air introduction to the refrigerator for compensating a pressure difference, a filter mounted to the opening and closing damper at an air introduction portion to be detachable with a packing cap for easy removal of noxious insects, microbes, and dust, and easy washing and replacement, and a packing member provided to the opening and closing damper for improving a sealing function to prevent cold air from leaking, quick compensation of the pressure difference, and eliminating difficulty in opening the door caused by the negative pressure.

Additional advantages, objects, and features of the disclosure will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a negative pressure preventive device 10 mounted to a refrigerator 100 to guide and introduce air to an evaporator 140 in the refrigerator 100, includes an air introduction pipe 20 formed in a refrigerator wall to have fastening flanges 21 on an insulating layer 130 between an inner wall 110 and an outer wall 120 of the refrigerator wall, an external air flow pipe 12 fastened to the air introduction pipe 20 having a vertical portion of a predetermined height and a diagonal portion connected to the vertical portion, an opening and closing damper 15 mounted to the external air flow pipe 12 with a hinge shaft 16 thereof passed through hinge holes 14 in a top side of the external air flow pipe 12, the opening and closing damper 15 including a packing member 17 in close contact with a circumference of an air introduction opening 13 for closing and opening an air flow, and a control lever 18 secured to the hinge shaft 16 exposed from an outer side of the air introduction pipe 20 to have gravity, and a filter cap 31 placed on the external air flow pipe 12 on an outside of the air introduction opening 13 having a filter 30 provided therein for preventing noxious insects and dust from entering into the refrigerator.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the disclosure and together with the description serve to explain the principle of the disclosure. In the drawings:

FIG. 1 illustrates a perspective view of a negative pressure preventive device in accordance with a preferred embodiment of the present invention.

FIG. 2 illustrates a section showing a negative pressure preventive device in accordance with a preferred embodiment of the present invention mounted to a refrigerator.

FIG. 3 illustrates a perspective view showing a negative pressure preventive device in accordance with a preferred embodiment of the present invention mounted to a machinery room of a refrigerator.

DESCRIPTION OF SPECIFIC EMBODIMENTS

Reference will now be made in detail to the specific embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

A negative pressure preventive device in accordance with a preferred embodiment of the present invention will be described with reference to the attached drawings for eliminating a negative pressure caused by shrinkage of external air introduced to a refrigerator when a refrigerator door is opened due to a low temperature in the refrigerator.

FIG. 1 illustrates a perspective view of a negative pressure preventive device in accordance with a preferred embodiment of the present invention, FIG. 2 illustrates a section showing a negative pressure preventive device in accordance with a preferred embodiment of the present invention mounted to a refrigerator, and FIG. 3 illustrates a perspective view showing a negative pressure preventive device in accordance with a preferred embodiment of the present invention mounted to a machinery room of a refrigerator.

Referring to FIGS. 1, 2, and 3, there is an air introduction pipe 20 formed in a refrigerator wall of a top of a refrigerator, the refrigerator wall having an outer plate 110 and an inner plate 120 of a metal or a resin with an insulating layer 130 disposed therebetween, for guiding and introducing air to an evaporator 140 in the refrigerator and fastening a negative pressure preventive device 10 to the top.

Though FIG. 3 illustrates the machinery room 150 provided on a top of the refrigerator 100 for mounting refrigerating machinery thereto, different from this, a refrigerator having no machinery room 150 provided on the top of the refrigerator may also be used.

The air introduction pipe 20 can be a unitary type in which fastening flanges 21 are formed on upper and lower sides of the air introduction pipe 20 as one unit with the air introduction pipe 20 for secure mounting of the air introduction pipe 20 in the inner and outer walls 110 and 120 and the inside insulating material 130 of the refrigerator 100, or can be a fabricated type in which the fastening flanges 21 are to couple to upper and lower sides of the air introduction pipe 20, respectively.

Referring to FIGS. 1 and 2, the negative pressure preventive device 10 includes a fastening flange 11 for fastening to the upper side fastening flange 21 of the air introduction pipe 20 with fastening bolts 40, an external air flow pipe 12 having a vertical portion of a predetermined height and a diagonal portion connected to the vertical portion, a hinge opening 14 at an end portion of an air introduction opening 13 of the an external air flow pipe 12 for mounting an opening and closing damper 15 thereto with a hinge shaft 16 for making the opening and closing damper 15 operated following movement of a control lever 18.

The opening and closing damper 15 includes a sealable packing member 17 in close contact with a circumference of the air introduction opening 13 for closing and opening an air flow, and a control lever 18 secured to the hinge shaft 16 exposed from an outer side of the air introduction pipe 20 for quick handling of the opening and closing damper 15 with a weight, for manual operation with the control lever 18, and quick operation of the opening and closing damper 15 with a gravity of the control lever 18.

And, the negative pressure preventive device 10 also includes a filter cap 31 placed on the external air flow pipe 12 on an outside of the air introduction opening 13 having a filter 30 provided therein for preventing noxious insects and dust from entering into the refrigerator 100.

Unexplained reference numeral 160 denotes a door on the refrigerator, and 32 denotes a clip for mounting the filter cap 31 to the external air flow pipe 12.

Of course, the negative pressure preventive device 10 can be provided to the machinery room 150 in FIG. 3 singly or in plural, or mounted to an appropriate position of the top or rear of the refrigerator 100.

Moreover, owing to the filter 30, the negative pressure preventive device 10 of the present invention can prevent refrigerated, or frozen food from deteriorating by the noxious insects, microbes, and dust carried into the refrigerator by the external air introduced to the refrigerator. And, by detachable mounting of the filter 30 with the filter cap 31 to the external air flow pipe 12 for making periodic wash and replacement of the filter 30 easy, the refrigerator can be maintained clean.

The operation and effects of the negative pressure preventive device 10 of the present invention will be described with reference to the attached drawings.

Referring to FIG. 3 showing the negative pressure preventive device 10 mounted to the machinery room of the refrigerator 100, the door 160 of the refrigerator 100 having the negative pressure preventive device 10 mounted to the machinery room is disposed for use by the user.

That is, when the user pulls the door 160 to open the door 160 of the refrigerator 100 in a cool and enclosed state, since the air is discharged from the refrigerator 100 causing a low pressure or a vacuum in the refrigerator 100, the external air is introduced to the refrigerator 100 through the negative pressure preventive device 10 at the top of the refrigerator 100.

In more detail, referring to FIG. 2, air suction from the air introduction pipe 20 and the external air flow pipe 12 by means of the vacuum formed by air discharge from the refrigerator 100 through the air introduction pipe 20 of the negative pressure preventive device 10 causes the opening and closing damper 15 hinged at the end of the external air flow pipe 12 to move inward, making the opening and closing damper 15 to space away from the air introduction opening 13, to open the air introduction opening 13.

Since the opening of the opening and closing damper 15 permits the external air to flow through the air introduction opening 13 and to be led to the evaporator 140, allowing the external air to be cooled down at the evaporator 140 and to be led to an inside of the refrigerator 100, a temperature rise of refrigerator 100 can be minimized.

In a case the door 160 of the refrigerator 100 is in a closed state, the opening and closing damper 15 and the control lever 18 connected to the opening and closing damper 15 with the hinge shaft 16 sustain a closed state of the opening and closing damper 15 such that the opening and closing damper 15 is not opened, and closed quickly even after opening of the opening and closing damper 15, to prevent the external air from introducing to the refrigerator 100 or the cool air from discharging to an outside of the refrigerator 100.

And, when the door 160 is opened after a certain period of time of use of the refrigerator 100, the air introduced to and locked in the refrigerator 100 by the closure of the door 160 heat exchanges with the cold air in the refrigerator 100 and shrinks to drop a pressure in the refrigerator 100, causing a pressure difference between the outside and the inside of the refrigerator 100. In this instance, a relatively high air pressure of the external air opens the opening and closing damper 15, to introduce the external air into the refrigerator 100 through the air introduction pipe 20, thereby compensating the pressure difference.

And, since the external air at a relatively high temperature is introduced to the refrigerator 100 through the evaporator 140, enabling quick cooling of the external air, maintenance of the temperature of the refrigerator 100 is easy, and quick pressure compensation about 10 seconds can be made, thereby permitting easy re-opening of the door 160.

At the time the negative pressure preventive device 10 is operated, the mounting of the negative pressure preventive device 10 over the evaporator 140 of the refrigerator 100 enables to minimize the temperature difference between the inside and the outside of the refrigerator 100 as the external high temperature air heat exchanges with the evaporator 140 in the refrigerator 100, to prevent dew formation from taking place when the external high temperature air crosses with the cold air in the refrigerator 100 owing to such an external air introduction process, to shorten a time period for re-opening the door 160 within a short time period.

The shortening of the re-opening time period can be adjusted by a size and a number of the negative pressure preventive devices 10, and cross sections of the external air flow pipe 12 and the air introduction pipe 20 can be any one of square and circle.

Especially, the control of opening and closing of the opening and closing damper 15 of the negative pressure preventive device 10 with gravity of the control lever 18 enables the quick returning or opening of the opening and closing damper 15.

An amount of air to be introduced to the refrigerator 100 which depends on the pressure difference between the outside and inside of the refrigerator 100 can be adjusted by an opening of the opening and closing damper 15.

That is, since the control lever 18 connected to the opening and closing damper 15 with the hinge shaft 16 provides gravity which is fixed weight, to control excessive opening of the opening and closing damper 15, thereby controlling excessive introduction of the external air, allowing introduction of a proper amount of the external air according to the pressure difference between the inside and outside of the refrigerator 100, a great inside temperature change of the refrigerator 100 caused by introduction a large amount of the external air within a short time can be prevented.

Above function is made by the control lever 18 which makes the quick closing and opening of the opening and closing damper 15, and since the quick pressure compensation enables quick elimination and compensation of the negative pressure formed due to shrink of the external air introduced to the refrigerator, the present invention is a useful invention as the problem of difficulty of door 160 opening can be solved, simply.

The filter 30 provided to the negative pressure preventive device 10 of the present invention for preventing the noxious insects, microbes, and dust from entering into the refrigerator 100 carried by the air introduced to the refrigerator 100 can prevent the refrigerated, or frozen food from deterioration, and the filter 30 detachably mounted to the external air flow pipe 12 with the filter cap 31 makes periodic wash and replacement of the filter 30 easy, thereby permitting to maintain the refrigerator clean.

The fastening of the filter cap 31 to the external air flow pipe 12 with the clip 32 enables to remove the filter cap 31 by opening the clip 32 and to wash and replace the filter 30 in a removed state of the filter cap 31. The filter 30 of soft sponge or unwoven fabric in the filter cap 31 can be provided with insecticide, insect repellent and aromatic agent for effective filtering of harmful microbes.

As has been described, the negative pressure preventive device in a refrigerator of the present invention has the following advantages.

Since the negative pressure preventive device in a refrigerator is mounted to the top of the refrigerator to introduce external air through the external air flow pipe and the air introduction pipe for introducing the air to the refrigerator, and to make quick opening and closing of the opening and closing damper for quick elimination of the inside and the outside temperature difference and minimizing the temperature change in the refrigerator by cooling the warm external air at the evaporator, smooth opening of the door can be achieved at the time of opening of the refrigerator by eliminating the negative pressure of the refrigerator and fabrication of the negative pressure preventive device in a refrigerator is easy owing to a simple structure.

Moreover, the prevention of entrance of the noxious insects, and dust carried by the external air introduced to the refrigerator for prevention of the negative pressure permits introduction of harmful substance to the refrigerator to enhance cleanness of the refrigerator, and the detachable filter cap permits easy washing and replacement of the filter.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. 

1. A negative pressure preventive device mounted to a refrigerator to guide and introduce air to an evaporator in the refrigerator, comprising: an air introduction pipe formed in a refrigerator wall to have fastening flanges on an insulating layer between an inner plate and an outer plate of the refrigerator wall; an external air flow pipe fastened to the air introduction pipe having a vertical portion of a predetermined height and a diagonal portion connected to the vertical portion; an opening and closing damper mounted to the external air flow pipe with a hinge shaft thereof passed through hinge holes in a top side of the external air flow pipe, the opening and closing damper including a packing member in close contact with a circumference of an air introduction opening for closing and opening an air flow, and a control lever secured to the hinge shaft exposed from an outer side of the air introduction pipe to have gravity; and a filter cap placed on the external air flow pipe on an outside of the air introduction opening having a filter provided therein for preventing noxious insects and dust from entering into the refrigerator.
 2. The negative pressure preventive device as claimed in claim 1, wherein the opening and closing damper includes the control lever for opening and closing the opening and closing damper with gravity.
 3. The negative pressure preventive device 10 as claimed in claim 1, wherein the negative pressure preventive device is mounted to the refrigerator singly or in plural.
 4. The negative pressure preventive device as claimed in claim 1, wherein the negative pressure preventive device is mounted to a top of the refrigerator to introduce external air to an evaporator through the negative pressure preventive device for preventing dew from forming by a temperature difference.
 5. The negative pressure preventive device as claimed in claim 1, wherein the external air flow pipe and the air introduction pipe have square or circular cross sections, respectively. 